Newcastle Disease Virus Virotherapy: Unveiling Oncolytic Efficacy and Immunomodulation

Abstract

In virotherapy, cancer cells are eradicated via viral infection, replication, and dissemination (oncolysis). Background: This study aims to evaluate the oncolytic potential of Newcastle disease virus (NDV) against colon cancer and explore the immune response associated with its therapeutic effects. Methods: NDV was tested for its oncolytic potential in colon cancer cell lines using MTT assays and apoptosis assessments. Tumor-induced mice were treated with NDV, tumor cell lysate (TCL), or a combination of both. After the euthanasia of murine subjects, an assessment of oncolytic efficacy was performed through flow cytometry analysis of murine blood and tumor tissue, targeting CD83, CD86, CD8, and CD4. An ELISA was also performed to examine interferon-gamma levels, interleukin-4 levels, interleukin-12 levels, and interleukin-10 levels in serum and spleen homogenate. Results: Cell viability was low in HCT116 and HT-29, indicating a cytotoxic effect in the MTT assay. NDV+TCL recorded the highest rate of cell death (56.72%). NDV+TCL had accelerated cell death after 48 h, reaching 58.4%. The flow cytometry analysis of the blood and tumor of mice with induced tumor treated with combined treatment revealed elevated levels of CD83, CD86, CD8, and CD4 (76.3, 66.9, 83.7, and 14.4%, respectively). The ELISA levels of IFN-γ, IL-4, and IL-12 in serum and the spleen homogenate were elevated (107.6 ± 9.25 pg/mL). In contrast, the expression of IL-10 was significantly reduced (1 ± 0.79).